#!/usr/bin/perl
#
# This is an answer, in comments and code, to the question:
# How to print data between tags from file sequentially?
# URL: https://perlmonks.org/index.pl?node_id=1217156
#
# LET'S EMBED THE FILE IN THE SCRIPT TO MAKE THIS EASY!
# YOUR FILE IS NOW ANYTHING AFTER __DATA__ AT THE END:
#
# open file
# open(FILE, "data.txt") or die("Unable to open file");
#
# ALWAYS START WITH THESE TWO LINES, FOR HELPFUL ERROR MESSAGES:

use strict;
use warnings;

# read file into an array

# PUT my BEFORE ALL VARIABLES TO PREVENT TYPOS LATER ON:
my @data = <DATA>;

# close file

# NOT NECESSARY ANYMORE:
# close(FILE);

# print file contents
foreach my $line (@data)

{
# THIS PRINTS EACH LINE, NOT WHAT YOU WANT:
# print $line;

# MODIFY EACH LINE WITH A REGEX* FOR CUSTOM PRINT!
# (*Short for "Regular Expression")
#
# Regex allows you to search and replace!
# s is the command and // are the quotes:
# s / FIND THIS TEXT / REPLACE WITH THIS /

	$line # For each line
	=~    # Do something like
	s/    # Search for
	<     # a < character
	[^>]+ # and one or more characters: [  ]+
	      # that are not a > character:  ^>
	>     # Followed by a > character
	      # (So anything like <whatever>)
	//gx; # Replace it with nothing: //
	      # g means replace all of them (global)
	      # x allows these comments because it is
	      # usually put on one line like this:
	      #
	      # $line =~ s/<[^>]+>//g; # COOL!

# NOW THE LINE IS CHANGED SO YOU CAN LOOK AT EACH LINE
# WITH =~ TO FIND OUT WHICH TEXT TO PRINT:

	# SIMPLE:

	if ($line =~ /ServerName/) {
		print "Computer: $line";
	}

	# SOMETHING MORE COMPLICATED:

	elsif ($line =~ /^  # IF LINE BEGINS WITH

			\d  # A NUMBER (DIGIT)

			/x  # (END REGEX, x JUST ALLOWS THESE COMMENTS)

			){  # IF THE ELSIF DECISION IS YES BECAUSE WE 
			    # SAW A NUMBER, THEN DO THIS:

		print "IP Address: $line";
	}

	# FIND WINDOWS OR LINUX OR MAC:
	# NOTE: i at the end of the next regex means
	# "case insensitive" so an "a" or "A" are equal.

        elsif ($line =~ /Windows|Linux|Mac/i) { 
                print "OS: $line";
        }

	# PRINT UNKNOWN LINES TOO SO YOU CAN SEE HOW 
	# TO ADD MORE DECISIONS ABOVE AND MAKE IT 
	# PRINT WHAT YOU WANT:

	else {
		print "UNKNOWN: $line";
	}
}

# THE EMBEDDED FILE:

__DATA__
<Answer type="string">ServerName</Answer>
<Answer type="string">10.10.10.11</Answer>
<Answer type="string">Windows Server 2012</Answer>